I. Field of the Invention
The present invention relates to inflatable body supports having a plurality of pockets which are alternately inflated and deflated to support adjacent sections of the human body. In particular, the present invention includes adaptations which are particularly suitable for coupling the apparatus to various systems of automotive vehicles.
II. Description of the Prior Art
It is well known to those who remain immobile for lengthy periods of time that the supporting sections of the body become uncomfortable and irritated after periods of only several hours. While bed-ridden hospital patients form the most severe example of immobility, this problem also faces drivers who must sit behind the wheel of an automobile or truck for several hours of driving without the opportunity to take breaks for the purpose of stimulating the circulation and for exercising the muscles which have supported the body.
It is also well known that the fatigue and discomfort which accompany long periods of immobility may contribute to automobile and truck accidents which are caused by the driver failing to maintain proper attention to his driving responsibilities. Therefore, while the present invention is designed primarily to aid in maintaining the comfort of a person who is required to be seated for long periods of time, such as in wheelchairs, it may also be useful for improving the comfort and safety record of long distance drivers.
The concept of pressure necrosis is well known in the prior art. Basically, the pressure exerted upon the muscle and skin surfaces which support the body weight for long periods of time causes a decrease in the circulation of blood in epidermal surfaces adjacent these areas. Certain smaller areas within these large pressure areas are more critical since the body bone structure is closer to the skin surface and excerts extra pressure thereupon, often causing the occurance of ulcers or bedsores near the sacrum of ischial tuberosities. Also, the movement of the pillow sections enhances air circulation between the pillow and the supported body sections, thereby cooling the body and inhibiting the onset of a rash.
The prior art contains many solutions to these problems. Nos, in U.S. Pat. No. 3,959,835, discloses the use of a plurality of air chambers, each interconnected with its neighbor through the use of a transversely extending hose having an inside diameter determined in order to control the rate of flow of the gas between adjacent chambers. Grant, in U.S. Pat. No. 3,199,124, discloses the use of an inflatable air mattress which includes a plurality of alternately inflatable air chambers, and also employs a plurality of smaller alternately inflatable chambers adjacent the feet of the reclining patient. Voelker, in U.S. Pat. No. 3,840,920, discloses the use of a non-resilient but flowable material and means for controlling the flowability of the material between compartments which comprise a mattress for pregnant mothers. Ducker, in U.S. Pat. No. 3,909,858, discloses a mattress having a plurality of alternately inflatable compartments which are separated by foam rubber cells.
Independently inflatable cushions have also been utilized in automotive seats. Vanderbilt, in U.S. Pat. No. 3,326,601, discloses the use of inflatable pockets arranged to form the back support for an automotive seat. Morrell, in U.S. Pat. No. 2,867,732, discloses the use of an automotive seat cushion employing a plurality of separately inflatable tubes which are mutually coupled by a tube which communicates through a center groove in each of the inflatable tubes. Burgin, in U.S. Pat. No. 3,982,786 discloses a chair having a plurality of specially interconnected cushion elements. These cushion elements are connected such that when the occupant sits in the chair the fluid in certain ones of the inflatable pockets are forced into other selected ones of the inflatable pockets for adjusting to the contour of the body shape of the occupant.
Parker, in U.S. Pat. No. 3,394,415, discloses an inflatable bed mattress constructed of a plurality of elongated inflatable cells which are completely independent and separate from each other and which do not include a unitary top communicating surface. Castagna, in U.S. Pat. No. 3,595,223, discloses a reclining couch having a plurality of manifolds which in turn form another plurality of inflatable chambers. Spence, in U.S. Pat. No. 3,308,491, discloses a seat cushion formed of a stretchable impermiable membrane surrounding a core formed of a hypoallergenic, nonfriable and jelly-like substance for evenly distributing the weight of the occupant over the entire surface of the contacting area.
While the prior art illustrates various designs of cushions with inflatable cells, the prior art does not illustrate the use of elements which are specifically adapted for economical construction and use, and for elements which are specifically adapted for coupling to and use with various support systems within automotive vehicles.
Thus, a first object of the present invention is to adapt the pump for economical construction and reliable performance through the use of a solenoid actuator operably coupled to at least one pumping chamber.
Another object of the present invention is to construct the inflatable pillow support to include a plurality of nondeflatable cells which serve as a minimum or residual support independent of the inflation or deflation status of the remaining inflatable cells.
A still further object of the present invention is to incorporate the use of a heat exchanger which controls the temperature and heat content of the fluid under pressure within the inflatable cells of the cushion by removing or adding heat obtained from various support systems of an automobile such as the engine cooling system and the air conditioning system.